Golf uses a system of nomenclature for strokes under par that is based on birds, with a score a single shot below par for the hole called a birdie, and two shots below par called an eagle. An eagle can be scored on a hole of any par, with differing difficulties on each depending on the skill level of the player.
How to Score an Eagle
There are two primary methods of scoring an eagle on a hole of golf. The first method of scoring an eagle is to reach the green in regulation, but do so by holing out. A par for a hole is determined by how many strokes it should take to reach a green and then adding a two-putt performance. So if a golfer hits it into the hole with an approach shot, it's two shots under par--an eagle. For some shorter par 4s and par 5s, a player with good distance can actually reach the green in one shot less than regulation, and then can score an eagle with a one-putt.
Holes in One
A hole in one is the most prestigious eagle that a player can score, and something that all golfers hope to accomplish. A hole in one eagle is scored by teeing off on a par 3 and hitting the first shot into the hole, without any penalty strokes. Players scoring a hole in one will often keep the ball as a trophy and treat their partners to the first round of drinks once off the course.
A 2 on a Par 4
Scoring a 2 on a par 4 is a difficult task for any golfer, as few courses feature drivable par 4s, meaning a player will almost certainly have to hit a good drive to be in position to shoot for the green, followed by a perfect approach to hole out.
A 3 on a Par 5
Eagles on par 5 holes are the most common among professionals, as many tournaments feature one or more par 5 holes that pros can reach in two shots. Making eagle on a par 5 is often an easier task for an average golfer than making one on a par 4, as players are more likely to find par 5s that can be reached in two shots, or approached close enough that the eagle shot is a short chip, than they are to find drivable par 4s.
A double eagle, also referred to as an albatross, is a very rare score, registered by sinking a ball in three fewer strokes than par. A double eagle can only be scored by holing out from distance, either by holing out with a drive on a par 4 or sinking the second shot on a reachable par 5.